New Delhi, Nov. 5 -- You are never truly prepared for the mental toll that an ugly exchange can extract. When it happens online, propagated largely by faceless screens that appear to have lowered an entire demographic's capacity for empathy, the effect can be exponentially worse.

Over the past week, I bore witness to one such instance of mindless, hostile trolls-and the trail of damage they left behind. More importantly, though, the incident highlightedhow ineffective much of social media's safety and reporting tools are, when you're in the thick of it.

The modus operandi was remarkably simple. Using a conveniently edited screenshot, a religious narrative was posted online by a clutch of social media accounts which, suspiciously enough,...